Closure device for a casing discharge port of a gun



N 9, 1966 AKE J. A, BlRATH CLOSURE DEVICE FOR A CASING DISCHARGE PORT OFA GUN 2 Sheets-Sheet 1 Filed April 1, 1965 INVENTOR AKE .JOHA/V ARTHURB/RATH A TTORNEYS Nov. 29, 1966 AKE J. A; BIRATH 3,288,029

CLOSURE DEVICE FOR A CASING DISCHARGE PORT OF A GUN Filed April 1, 19652 Sheets-Sheet 2 INVENTOR XKE JOHAN ARTHUR SIR/4TH Arrokus Ts UnitedStates Patent Ofiice 3,288,029 Patented Nov. 29, 1966 3 288 029 CLOSUREDEVICE FOR A CASING DISCHARGE PORT OF A GUN Ake Johan Arthur Birath,Bofors, Sweden, assignor to Aktiebolaget Bofors, Bofors, Sweden, acorporation of Sweden Filed Apr. 1, 1965, Ser. No. 444,627 Claimspriority, application Sweden, Apr. 8, 1964,

- 4,359/64 5 Claims. (Cl. 8933) The present invention relates to adevice for opening and closing a closure member such as a door for aport in a protective wall encasing the loading and cartridge casingejection mechanism of a gun, in particular an automatic recoiling gun.

With movable guns, the vital operational parts of which are enclosed byarmor-plating and the empty cartridge casings, of which, are rearwardlyejected after the firing of each round, it is of great importance that adischarge port for ejection of the empty casings through the portion ofthe protective wall located behind the ejection mechanism is open onlyfor the short period of time required for the passage of an ejectedcasing. Obviously,

a prolonged opening of the port entails the danger of damage to the gunby pieces of material propelled through the port and against the gunparts to be protected by the protective wall.

It is an object of the invention to provide a port control device whichuncovers the port for the passage of an empty cartridge casing throughthe wall just before the ejection of the casing from the cartridgechamber of the gun barrel and while the casing is moving along acartridge casing guide extending rearwardly of the barrel, and whichrecloses the port immediately after the passage of the ejected casingtherethrough, the device being actuated automatically in dependence uponthe recoil of the gun and the ejection of a casing.

To attain this object of the invention and other objects to be pointedout hereinafter, the device comprises, in combination, a closure membersuch as a door for opening and closing the port, an energy storing meanslinked to the door to apply a force thereto actuating the door to moveit from an open position to a closed position, the energy storing meansbeing arranged to store, during a motion of the door from the closed tothe open position, the energy necessary for closing the door; a memberfor moving the door from the closed to the open position, said memberincluding a first pawl coupling means arranged for releasablecooperation with a gun component which is movable during the operationalcycle of the gun between the firing of two successive rounds shortlyprior to the rearwardly ejection of an empty cartridge casing,preferably a gun component which is movable together with the gun barrelduring the run-out and run-in movement thereof due to the recoil. Thisgun component has a movable actuating member arranged to cooperate withsaid first pawl coupling means in the position thereof in which the dooroccupies its closed position so as to engage the member for moving thedoor into the open position and to be released from cooperation withsaid pawl coupling means after the door has been brought into openposition. A second pawl coupling means is arranged to retain the door inthe open position against the action of the force executed on the doorby said energy storing means and comprises a first coupling memberconnected to the door and a second coupling member connected to acoupling releasing means, said coupling releasing means being pivotalinto and out of the path of a casing ejected from the barrel towards andthrough the port to release said second pawl coupling when actuated byan empty casing during the ejection thereof.

With such a device, the discharge port will be opened by action of amovable gun component actuating the door shortly before the ejection ofa casing during a firing cycle. The door will then be retained in openposition by action of the second pawl coupling means, the first pawlcoupling means after the opening of the door having released the memberfor opening the door from its cooperation with the actuating member ofthe reciprocating gun component. Thus, the door will be retained in openposition during the following ejection of the casing; the casing, whenmoving rearwardly from the cartridge chamber, actuating the couplingreleasing means of the second pawl coupling means to release the doorand to free it for return to closed position by action of the force ofthe energy storing means.

The releasing means of the second pawl coupling, for obvious reasons, ispreferably arranged with in the space closed by the door and, if this isthe case, the empty casing may strike against the releasing means beforehaving passed through the port and past the door. To prevent a closingof the door so early that it is hit by the casing or even prevents thecasing from passing the port, the second pawl coupling is arranged, in apreferred embodiment according to the invention, in the manner of amechanical escapement. The component of the pawl coupling connected tothe door and also as the component thereof connected to the couplingreleasing means comprises each two stop noses, arranged for pairwisecoopera-tion. More specifically, the components of the coupling comprisetwo first stop noses, one on each of the two components, arranged formutual cooperation to hold the door in the open position after themotion thereof into this position by the action of the actuating memberof the reciprocating or recoiling gun component as long as the releasingmeans is still protruding into the path of an ejected casing, and thetwo second stop noses, one on each of the two components, arrangedrelative to each other so as to engage each other after thedisengagement of the first two noses when the releasing means, by theaction of a casing, is swung out of the path of the casing. The twocomponents of the coupling are thus entirely disengaged from each otherwhen the releasing means returns to its previous position clear of thepath of an ejected casing. The releasing means is actuated by adirectional force tending to hold it in this position.

The invention will become more clearly apparent from the followingdescription of a preferred embodiment as illustrated in the accompanyingdrawings in which:

FIG. 1 is a perspective view showing a device according to the inventionin a preferred embodiment thereof;

FIGS. 2-6 diagrammatically illustrate components for opening the door independence of actuating means reciprocating together with the gunbarrel, and the energy storing means for closing the door after ejectionof a casing and charged during the opening of the door; and

FIGS. 79 illustrate the releasing means for the door to move into closedposition after the ejection of a casing.

FIG. 1 illustrates components of the device according to the inventionarranged in part on a support 1, a gun barrel 2, a breech ring 3 and acartridge ramming guide 4 for cartridges to be fired. The gun barrel 2,during firing, perfonns a recoil movement in its longitudinal directionin relation to the support. The gun components illustrated in FIG. 1 areenclosed by armor plate 5 comprising a rear wall 6 having an outlet port7 for empty casings ejected rearwardly from the cartridge chamber of thegun barrel along a casing guide 8. A door 10 is hinged to the rear wall6 by a hinge 9, the

door being pivotal between the position illustrated in FIG. 1 in whichthe port 7 is closed thereby, to a position illustrated in FIGS. 7 and 8in which the passage through the wall is open for a casing movingbackwardly along the casing guide 8.

Normally, the door is held in its closed position actuated by a forceapplied thereto by an energy storing means, which, in its simplest form,may comprise a spring mechanism, against the action of which the doormay be opened. As illustrated, a spring 12, FIG. 6, arranged in a springhousing 11, abuts at one end against a wall of the housing secured tothe support 1, and at the other end against a collar 13 of adisplaceable rod 14. This rod 14 is connected by links 15, 16 and 17,and pivotal levers 18 and 19 to a bracket 20 on the door. Thus, the dooris pivotal from the closed to the open position and vice versa by amovement of rod 14 in the respective direction, spring 12 biasing thedoor into its closed position.

The means for opening the door, in this embodiment, are so arranged thatthe door is opened during a forward motion of the gun barrel and thecomponents connected thereto, and these means are common to the meansfor closing the door, except for the means directly affecting storing ofenergy for closing the door, namely spring housing 11, spring 12 andcollar 13. The rod 14, which is thus linked to the door by links 15, 16and 17 and pivotal arms 18 and 19, has an extension 21 extending throughthe housing 11. The forward free end of the extension mounts a couplingmeans including a pivotal pawl 27 which cooperates with an actuatingmember 23 attached to a component, which participates in the recoilmovement of the gun barrel.

In the embodiment as illustrated, this actuating member 23 is secured toa rod 24 which is lengthwise displaceable in a bracket 25 against theaction of a shock absorbing spring 26. The actuating member 23, isarranged relative to the pawl 27 so as to engage this pawl when movingbackwardly to a rear position, and is then taking the rod 14 with itforwardly, while at the same time loading the spring 12, whereby thedoor is opened during a following run-in of the barrel. The pawl 27 isactuated by a spring 22 to a position to engage with the actuatingmember 23 (FIG. 4).

A coupling releasing means, as illustrated, comprise an edge defining acut-out 28 in a bracket 29 secured to the support 1. This edge islocated in the way of the pawl 27 so as to move the same out ofengagement with the actuating member 23 against the action of spring 22when the actuating member, after having returned from the rearward orrecoil position, has reached a certain front position and the door isconsequently opened.

After the release of the pawl 27, the door is prevented from beingreturned into its closed position by action of the spring 12 by a secondpawl coupling, an embodiment of which is illustrated in detail in FIGS.7, 8 and 9. This second pawl coupling locks the door in the openposition shortly before the pawl 27 is released from the actuatingmember 23 by action of the edge of cut-out 28. The second couplingcomprises a pawl 31 carried by a pivot 30 secured to arm 19. Pawl 31 hastwo noses, 32 and 33, one of which cooperates with a nose 34 and theother with a nose 35 of a coupling member 36 which is pivotal about apivot 37 mounted on a coupling releasing means 38 arranged to be swunginto and out of the way of a cartridge casing along the casing guide 8.This coupling releasing means 38 is normally held in a positionextending into the guide by action of a spring 40 arranged between anabutment member 39 and the coupling releasing means 38 so as to protrudeinto the path of a cartridge casing 41 being ejected from the cartridgechamber of the barrel 3 towards the port 7, as illustrated in FIGS. 7and 9, but when it is passed by an ejected casing, FIG. 8.

When the door is moved into open position by the action of the actuatingmember 23 carrying the rod 21 forwardly and the coupling between theactuating member 23 and rod 21 is released by the edge of cut-out 28freeing the pawl 27, the nose 32 of the second coupling moves intoengagement with nose 34 of coupling member 36, as illustrated by arrowsin FIG. 7. When the pawl 27 is released from the actuating member 23 asillustrated in FIG. 6, the door is prevented from moving back intoclosed position by action of the spring 24 by nose 32 engaging nose 34.However, when a casing 41 is thereafter ejected through the casing guide8, the coupling releasing means 38 is, as illustrated in FIG. 8, moveddownwardly, that is, out of the way of the casing. During this movementof the coupling releasing means 28, nose 35 is moved into a position tocatch the nose 33 in the same way as in a conventional mechanicalescapement, the door thus still being prevented from being brought intoclosed position by action of spring 12.

When having been passed by the casing, the coupling releasing means 38returns into the space within the cartridge casing guide 3, by action ofspring 41 whereby the nose 35 releases nose 33, the second couplingmeans 31 to 36 of the device thus being released to free the door forbeing moved back into closed position by action of spring 12, asillustrated in FIG. 8. Thus, the starting position of the device asillustrated in FIG. 1 is restored.

While the invention has been described in detail with respect to certainnow preferred examples and embodiments of the invention, it will beunderstood by those skilled in the art, after understanding theinvention, that various changes and modifications may be made withoutdeparting from the spirit and scope of the invention, and it isintended, therefore, to cover all such changes and modifications in theappended claims.

What is claimed is:

1. A closure device for opening and closing a discharge port for emptyshell casings ejected by the ejecting mechanism of a gun, said devicecomprising, in combination, a movable closure member for opening andclosing a casing discharge port in a protective wall for a gun; energystoring means coupled to the closure member, said means being loaded byan opening of said closure member and urging the same into its closedposition; a linkage means coupled with the closure member for moving thesame from the closed position into the open position; a casingejectingmechanism including an actuating member movable in response to anactivation of said ejection mechanism by firing a round from the gun;first coupling means supported by said linkage means and coupling thesame to said actuating member in the closed position of the closuremember for moving said member into its open position by a movement ofsaid actuating member; first coupling-release means coacting saidcoupling means for releasing the same from the actuating member uponmovement of the closure member into the open position; second couplingmeans coacting with said closure member for holding the same in its openposition against the action of said energy-storing means; and secondcouplingrelease means coacting with said second coupling means torelease the latter for return of the closure member into its closingposition by the action of said energy-storing means, said secondcoupling-release means being activated by engagement with an ejectedcasing moving toward said port and return into an inactive position uponpassage of the casing.

2. A device according to claim 1, wherein said ejection mechanismcomprises a guide means for guiding an ejected casing toward said port,and wherein said second coupling-release means comprises a pivotallymounted actuating arm biased to protrude into the path of a casingpassing through said guide means, engagement of said arm with a passingejected casing causing a pivotal movement of the arm, said pivotalmovement activating said coupling-release means for release of thesecond coupling means.

3. A device according to claim 1, wherein said second coupling meanscomprise an escape mechanism, said mechanism including a member linkedto said linkage means and a means linked to said second coupling-releasemeans, each of said two members having a first and a second catch nose,said first noses of the two members engaging each other to hold theclosure member in its open position when and while said secondcouplingrelease means are inactive and being released when said secondcoupling-release means are activated by said engagement with an ejectedcasing, and said second noses of the two members engaging each otherwhen the second coupling-release means are activated and being releasedwhen the second coupling-release means return into the inactive positionupon passage of the casing.

means biasing said second coupling-release means into the inactiveposition.

5. A device according to claim 3, wherein said second coupling-releasemeans comprise a pivotally mounted actuating arm biased to protrude intothe path of an ejected casing, engagement with a passing ejected casingpivoting said arm out of the path of the casing, said protruding armposition constituting the inactive positive of the secondcoupling-release means, and said pivoted arm position constituting theactivated position of the second couplingrelease means.

No references cited.

BENJAMIN A. BORCHELT, Primary Examiner.

4. A device according to claim 3 and comprising spring 15 S. C. BENTLEY,Assistant Examiner.

1. A CLOSURE DEVICE FOR OPENING AND CLOSING A DISCHARGE PORT FOR EMPTYSHEELL CASINGS EJECTED BY THE EJECTING MECHANISM FOR A GUN, SAID DEVICECOMPRISING, IN COMBINATION, A MOVABLE CLOSURE MEMBER FOR OPENING ANDCLOSING A CASING DISCHARGE PORT IN A PROTECTIVE WALL FOR A GUN; ENERGYSTORING MEANS COUPLED TO THE CLOSURE MEMBER, SAID MEANS BEING LOADED BYAN OPENING OF SAID CLOSURE MEMBER AND URGING THE SAME INTO ITS CLOSEDPOSITION; A LINKAGE MEANS COUPLED WITH THE CLOSURE MEMBER FOR MOVING THESAME FROM THE CLOSED POSITION INTO THE OPEN POSITION; A CASINGEJECTINGMECHANISM INCLUDING AN ACTUATING MEMBER MOVABLE IN RESPONSE TO ANACTIVATION OF SAID EJECTION MECHANISM BY FIRING A ROUND FROM THE GUN;FIRST COUPLING MEANS SUPPORTED BY SAID LINKAGE MEANS AND COUPLING THESAME TO SAID ACTUATING MEMBER IN THE CLOSED POSITION OF THE CLOSUREMEMBER FOR MOVING SAID MEMBER INTO ITS OPEN